1. Field of the Invention
The present invention relates to a perpendicular magnetic write head provided with a magnetic pole and a side shield layer, and a magnetic write device mounted with the same.
2. Description of the Related Art
In recent years, with improvement in the areal recording density of a magnetic recording medium (hereafter, referred to as “recording medium”) which is typified by a hard disk, performance improvement in a magnetic write head is desired. In response to such a trend, as a writing method of the magnetic write head, in substitution for the longitudinal magnetic writing method in which the direction of a signal magnetic field is set to the in-plane direction of the recording medium, the perpendicular magnetic writing method in which the direction of the signal magnetic field is set to the direction intersecting the plane of the recording medium has attracted attention. This is because, there are such advantages that the linear recording density improves, and a recording medium on which information has been already recorded is less subjected to heat fluctuation.
A magnetic write head of the perpendicular magnetic writing method (hereafter, referred to as “perpendicular magnetic write head”) is provided with a thin film coil for generating magnetic flux, and a main magnetic pole layer leading the magnetic flux which is generated in the thin film coil, to a recording medium. This main magnetic pole layer includes a tip portion (magnetic pole) having a fine width, which generates a magnetic field (perpendicular magnetic field) for writing.
In order to deal with the high recording density while suppressing spread of the perpendicular magnetic field, for a configuration of the perpendicular magnetic write head, the configuration in which a side shield layer is arranged on both sides of a magnetic pole with a gap in between, in a write track width direction has been taken into consideration (for example, see Japanese Unexamined Patent Publication Nos. 2004-326990, 2004-022004, and 2005-310363).
Under this situation, since there is such a tendency that the areal recording density of a recording medium increases more and more today, it is highly desired to make the configuration of the perpendicular magnetic write head more suitable. However, in the perpendicular magnetic write head of the related art, which includes the side shield layer, the relationship between ensuring magnitude of the perpendicular magnetic field and suppression of spread of the perpendicular magnetic field is a trade-off. Thus, it is difficult to realize both ensuring magnitude of the perpendicular magnetic field and suppression of spread of the perpendicular magnetic field. This means that there is still room for improvement in the writing performance.
For these reasons, it is highly desired to improve the writing performance by realizing both ensuring magnitude of the perpendicular magnetic field and suppression of spread of the perpendicular magnetic field.